1 /* 2 * ---------------------------------------------------------------------------- 3 * "THE BEER-WARE LICENSE" (Revision 42): 4 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you 5 * can do whatever you want with this stuff. If we meet some day, and you think 6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 7 * ---------------------------------------------------------------------------- 8 */ 9 10 #include <sys/cdefs.h> 11 __FBSDID("$FreeBSD$"); 12 13 #include <sys/param.h> 14 #include <sys/jail.h> 15 16 #include <netinet/in.h> 17 #include <arpa/inet.h> 18 19 #include <err.h> 20 #include <errno.h> 21 #include <grp.h> 22 #include <login_cap.h> 23 #include <paths.h> 24 #include <pwd.h> 25 #include <stdio.h> 26 #include <stdlib.h> 27 #include <string.h> 28 #include <unistd.h> 29 30 static void usage(void); 31 extern char **environ; 32 33 #define GET_USER_INFO do { \ 34 pwd = getpwnam(username); \ 35 if (pwd == NULL) { \ 36 if (errno) \ 37 err(1, "getpwnam: %s", username); \ 38 else \ 39 errx(1, "%s: no such user", username); \ 40 } \ 41 lcap = login_getpwclass(pwd); \ 42 if (lcap == NULL) \ 43 err(1, "getpwclass: %s", username); \ 44 ngroups = NGROUPS; \ 45 if (getgrouplist(username, pwd->pw_gid, groups, &ngroups) != 0) \ 46 err(1, "getgrouplist: %s", username); \ 47 } while (0) 48 49 int 50 main(int argc, char **argv) 51 { 52 login_cap_t *lcap = NULL; 53 struct jail j; 54 struct passwd *pwd = NULL; 55 struct in_addr in; 56 gid_t groups[NGROUPS]; 57 int ch, i, iflag, Jflag, lflag, ngroups, uflag, Uflag; 58 char path[PATH_MAX], *username, *JidFile; 59 static char *cleanenv; 60 const char *shell, *p = NULL; 61 FILE *fp; 62 63 iflag = Jflag = lflag = uflag = Uflag = 0; 64 username = JidFile = cleanenv = NULL; 65 fp = NULL; 66 67 while ((ch = getopt(argc, argv, "ilu:U:J:")) != -1) { 68 switch (ch) { 69 case 'i': 70 iflag = 1; 71 break; 72 case 'J': 73 JidFile = optarg; 74 Jflag = 1; 75 break; 76 case 'u': 77 username = optarg; 78 uflag = 1; 79 break; 80 case 'U': 81 username = optarg; 82 Uflag = 1; 83 break; 84 case 'l': 85 lflag = 1; 86 break; 87 default: 88 usage(); 89 } 90 } 91 argc -= optind; 92 argv += optind; 93 if (argc < 4) 94 usage(); 95 if (uflag && Uflag) 96 usage(); 97 if (lflag && username == NULL) 98 usage(); 99 if (uflag) 100 GET_USER_INFO; 101 if (realpath(argv[0], path) == NULL) 102 err(1, "realpath: %s", argv[0]); 103 if (chdir(path) != 0) 104 err(1, "chdir: %s", path); 105 memset(&j, 0, sizeof(j)); 106 j.version = 0; 107 j.path = path; 108 j.hostname = argv[1]; 109 if (inet_aton(argv[2], &in) == 0) 110 errx(1, "Could not make sense of ip-number: %s", argv[2]); 111 j.ip_number = ntohl(in.s_addr); 112 if (Jflag) { 113 fp = fopen(JidFile, "w"); 114 if (fp == NULL) 115 errx(1, "Could not create JidFile: %s", JidFile); 116 } 117 i = jail(&j); 118 if (i == -1) 119 err(1, "jail"); 120 if (iflag) { 121 printf("%d\n", i); 122 fflush(stdout); 123 } 124 if (Jflag) { 125 if (fp != NULL) { 126 fprintf(fp, "%d\t%s\t%s\t%s\t%s\n", 127 i, j.path, j.hostname, argv[2], argv[3]); 128 (void)fclose(fp); 129 } else { 130 errx(1, "Could not write JidFile: %s", JidFile); 131 } 132 } 133 if (username != NULL) { 134 if (Uflag) 135 GET_USER_INFO; 136 if (lflag) { 137 p = getenv("TERM"); 138 environ = &cleanenv; 139 } 140 if (setgroups(ngroups, groups) != 0) 141 err(1, "setgroups"); 142 if (setgid(pwd->pw_gid) != 0) 143 err(1, "setgid"); 144 if (setusercontext(lcap, pwd, pwd->pw_uid, 145 LOGIN_SETALL & ~LOGIN_SETGROUP) != 0) 146 err(1, "setusercontext"); 147 login_close(lcap); 148 } 149 if (lflag) { 150 if (*pwd->pw_shell) 151 shell = pwd->pw_shell; 152 else 153 shell = _PATH_BSHELL; 154 if (chdir(pwd->pw_dir) < 0) 155 errx(1, "no home directory"); 156 setenv("HOME", pwd->pw_dir, 1); 157 setenv("SHELL", shell, 1); 158 setenv("USER", pwd->pw_name, 1); 159 if (p) 160 setenv("TERM", p, 1); 161 } 162 if (execv(argv[3], argv + 3) != 0) 163 err(1, "execv: %s", argv[3]); 164 exit(0); 165 } 166 167 static void 168 usage(void) 169 { 170 171 (void)fprintf(stderr, "%s%s\n", 172 "usage: jail [-i] [-J jid_file] [-l -u username | -U username]", 173 " path hostname ip-number command ..."); 174 exit(1); 175 } 176